IDECDROM.cc

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#include "IDECDROM.hh"
#include "DeviceConfig.hh"
#include "MSXMotherBoard.hh"
#include "FileContext.hh"
#include "FileException.hh"
#include "RecordedCommand.hh"
#include "CommandException.hh"
#include "TclObject.hh"
#include "CliComm.hh"
#include "endian.hh"
#include "serialize.hh"
#include <algorithm>
#include <cassert>
#include <cstdio>
#include <memory>

using std::string;
using std::vector;

namespace openmsx {

class CDXCommand final : public RecordedCommand
{
public:
        CDXCommand(CommandController& commandController,
                   StateChangeDistributor& stateChangeDistributor,
                   Scheduler& scheduler, IDECDROM& cd);
        void execute(span<const TclObject> tokens,
                TclObject& result, EmuTime::param time) override;
        string help(const vector<string>& tokens) const override;
        void tabCompletion(vector<string>& tokens) const override;
private:
        IDECDROM& cd;
};


IDECDROM::IDECDROM(const DeviceConfig& config)
        : AbstractIDEDevice(config.getMotherBoard())
        , name("cdX")
{
        cdInUse = getMotherBoard().getSharedStuff<CDInUse>("cdInUse");

        unsigned id = 0;
        while ((*cdInUse)[id]) {
                ++id;
                if (id == MAX_CD) {
                        throw MSXException("Too many CDs");
                }
        }
        name[2] = char('a' + id);
        (*cdInUse)[id] = true;
        cdxCommand = std::make_unique<CDXCommand>(
                getMotherBoard().getCommandController(),
                getMotherBoard().getStateChangeDistributor(),
                getMotherBoard().getScheduler(), *this);

        senseKey = 0;

        remMedStatNotifEnabled = false;
        mediaChanged = false;

        byteCountLimit = 0; // avoid UMR in serialize()
        transferOffset = 0;
        readSectorData = false;

        getMotherBoard().getMSXCliComm().update(CliComm::HARDWARE, name, "add");
}

IDECDROM::~IDECDROM()
{
        getMotherBoard().getMSXCliComm().update(CliComm::HARDWARE, name, "remove");

        unsigned id = name[2] - 'a';
        assert((*cdInUse)[id]);
        (*cdInUse)[id] = false;
}

bool IDECDROM::isPacketDevice()
{
        return true;
}

const std::string& IDECDROM::getDeviceName()
{
        static const std::string NAME = "OPENMSX CD-ROM";
        return NAME;
}

void IDECDROM::fillIdentifyBlock(AlignedBuffer& buf)
{
        // 1... ....: removable media
        // .10. ....: fast handling of packet command (immediate, in fact)
        // .... .1..: incomplete response:
        //            fields that depend on medium are undefined
        // .... ..00: support for 12-byte packets
        buf[0 * 2 + 0] = 0xC4;
        // 10.. ....: ATAPI
        // ...0 0101: CD-ROM device
        buf[0 * 2 + 1] = 0x85;

        // ...1 ....: Removable Media Status Notification feature set supported
        buf[ 83 * 2 + 0] = 0x10;
        // ...1 ....: Removable Media Status Notification feature set enabled
        buf[ 86 * 2 + 0] = remMedStatNotifEnabled * 0x10;
        // .... ..01: Removable Media Status Notification feature set supported (again??)
        buf[127 * 2 + 0] = 0x01;
}

unsigned IDECDROM::readBlockStart(AlignedBuffer& buf, unsigned count)
{
        assert(readSectorData);
        if (file.is_open()) {
                //fprintf(stderr, "read sector data at %08X\n", transferOffset);
                file.seek(transferOffset);
                file.read(buf, count);
                transferOffset += count;
                return count;
        } else {
                //fprintf(stderr, "read sector failed: no medium\n");
                // TODO: Check whether more error flags should be set.
                abortReadTransfer(0);
                return 0;
        }
}

void IDECDROM::readEnd()
{
        setInterruptReason(I_O | C_D);
}

void IDECDROM::writeBlockComplete(AlignedBuffer& buf, unsigned count)
{
        // Currently, packet writes are the only kind of write transfer.
        assert(count == 12);
        (void)count; // avoid warning
        executePacketCommand(buf);
}

void IDECDROM::executeCommand(byte cmd)
{
        switch (cmd) {
        case 0xA0: // Packet Command (ATAPI)
                // Determine packet size for data packets.
                byteCountLimit = getByteCount();
                //fprintf(stderr, "ATAPI Command, byte count limit %04X\n",
                //      byteCountLimit);

                // Prepare to receive the command.
                startWriteTransfer(12);
                setInterruptReason(C_D);
                break;

        case 0xDA: // ATA Get Media Status
                if (remMedStatNotifEnabled) {
                        setError(0);
                } else {
                        // na WP MC na MCR ABRT NM obs
                        byte err = 0;
                        if (file.is_open()) {
                                err |= 0x40; // WP (write protected)
                        } else {
                                err |= 0x02; // NM (no media inserted)
                        }
                        // MCR (media change request) is not yet supported
                        if (mediaChanged) {
                                err |= 0x20; // MC (media changed)
                                mediaChanged = false;
                        }
                        //fprintf(stderr, "Get Media status: %02X\n", err);
                        setError(err);
                }
                break;

        case 0xEF: // Set Features
                switch (getFeatureReg()) {
                case 0x31: // Disable Media Status Notification.
                        remMedStatNotifEnabled = false;
                        break;
                case 0x95: // Enable  Media Status Notification
                        setLBAMid(0x00); // version
                        // .... .0..: capable of physically ejecting media
                        // .... ..0.: capable of locking the media
                        // .... ...X: previous enabled state
                        setLBAHigh(remMedStatNotifEnabled);
                        remMedStatNotifEnabled = true;
                        break;
                default: // other subcommands handled by base class
                        AbstractIDEDevice::executeCommand(cmd);
                }
                break;

        default: // all others
                AbstractIDEDevice::executeCommand(cmd);
        }
}

void IDECDROM::startPacketReadTransfer(unsigned count)
{
        // TODO: Recompute for each packet.
        // TODO: Take even/odd stuff into account.
        // Note: The spec says maximum byte count is 0xFFFE, but I prefer
        //       powers of two, so I'll use 0x8000 instead (the device is
        //       free to set limitations of its own).
        unsigned packetSize = 512; /*std::min(
                byteCountLimit, // limit from user
                std::min(sizeof(buffer), 0x8000u) // device and spec limit
                );*/
        unsigned size = std::min(packetSize, count);
        setByteCount(size);
        setInterruptReason(I_O);
}

void IDECDROM::executePacketCommand(AlignedBuffer& packet)
{
        // It seems that unlike ATA which uses words at the basic data unit,
        // ATAPI uses bytes.
        //fprintf(stderr, "ATAPI Packet:");
        //for (unsigned i = 0; i < 12; i++) {
        //      fprintf(stderr, " %02X", packet[i]);
        //}
        //fprintf(stderr, "\n");

        readSectorData = false;

        switch (packet[0]) {
        case 0x03: { // REQUEST SENSE Command
                // TODO: Find out what the purpose of the allocation length is.
                //       In practice, it seems to be 18, which is the amount we want
                //       to return, but what if it would be different?
                //int allocationLength = packet[4];
                //fprintf(stderr, "  request sense: %d bytes\n", allocationLength);

                const int byteCount = 18;
                startPacketReadTransfer(byteCount);
                auto& buf = startShortReadTransfer(byteCount);
                for (int i = 0; i < byteCount; i++) {
                        buf[i] = 0x00;
                }
                buf[ 0] = 0xF0;
                buf[ 2] = senseKey >> 16; // sense key
                buf[12] = (senseKey >> 8) & 0xFF; // ASC
                buf[13] = senseKey & 0xFF; // ASQ
                buf[ 7] = byteCount - 7;
                senseKey = 0;
                break;
        }
        case 0x43: { // READ TOC/PMA/ATIP Command
                //bool msf = packet[1] & 2;
                int format = packet[2] & 0x0F;
                //int trackOrSession = packet[6];
                //int allocLen = (packet[7] << 8) | packet[8];
                //int control = packet[9];
                switch (format) {
                case 0: { // TOC
                        //fprintf(stderr, "  read TOC: %s addressing, "
                        //      "start track %d, allocation length 0x%04X\n",
                        //      msf ? "MSF" : "logical block",
                        //      trackOrSession, allocLen);
                        setError(ABORT);
                        break;
                }
                case 1: // Session Info
                case 2: // Full TOC
                case 3: // PMA
                case 4: // ATIP
                default:
                        fprintf(stderr, "  read TOC: format %d not implemented\n", format);
                        setError(ABORT);
                }
                break;
        }
        case 0xA8: { // READ Command
                int sectorNumber = Endian::read_UA_B32(&packet[2]);
                int sectorCount  = Endian::read_UA_B32(&packet[6]);
                //fprintf(stderr, "  read(12): sector %d, count %d\n",
                //      sectorNumber, sectorCount);
                // There are three block sizes:
                // - byteCountLimit: set by the host
                //     maximum block size for transfers
                // - byteCount: determined by the device
                //     actual block size for transfers
                // - transferCount wrap: emulation thingy
                //     transparent to host
                //fprintf(stderr, "byte count limit: %04X\n", byteCountLimit);
                //unsigned byteCount = sectorCount * 2048;
                //unsigned byteCount = sizeof(buffer);
                //unsigned byteCount = packetSize;
                /*
                if (byteCount > byteCountLimit) {
                        byteCount = byteCountLimit;
                }
                if (byteCount > 0xFFFE) {
                        byteCount = 0xFFFE;
                }
                */
                //fprintf(stderr, "byte count: %04X\n", byteCount);
                readSectorData = true;
                transferOffset = sectorNumber * 2048;
                unsigned count = sectorCount * 2048;
                startPacketReadTransfer(count);
                startLongReadTransfer(count);
                break;
        }
        default:
                fprintf(stderr, "  unknown packet command 0x%02X\n", packet[0]);
                setError(ABORT);
        }
}

void IDECDROM::eject()
{
        file.close();
        mediaChanged = true;
        senseKey = 0x06 << 16; // unit attention (medium changed)
        getMotherBoard().getMSXCliComm().update(CliComm::MEDIA, name, {});
}

void IDECDROM::insert(const string& filename)
{
        file = File(filename);
        mediaChanged = true;
        senseKey = 0x06 << 16; // unit attention (medium changed)
        getMotherBoard().getMSXCliComm().update(CliComm::MEDIA, name, filename);
}


// class CDXCommand

CDXCommand::CDXCommand(CommandController& commandController_,
                       StateChangeDistributor& stateChangeDistributor_,
                       Scheduler& scheduler_, IDECDROM& cd_)
        : RecordedCommand(commandController_, stateChangeDistributor_,
                          scheduler_, cd_.name)
        , cd(cd_)
{
}

void CDXCommand::execute(span<const TclObject> tokens, TclObject& result,
                         EmuTime::param /*time*/)
{
        if (tokens.size() == 1) {
                auto& file = cd.file;
                result.addListElement(cd.name + ':',
                                      file.is_open() ? file.getURL() : string{});
                if (!file.is_open()) result.addListElement("empty");
        } else if ((tokens.size() == 2) &&
                   ((tokens[1] == "eject") || (tokens[1] == "-eject"))) {
                cd.eject();
                // TODO check for locked tray
                if (tokens[1] == "-eject") {
                        result = "Warning: use of '-eject' is deprecated, "
                                 "instead use the 'eject' subcommand";
                }
        } else if ((tokens.size() == 2) ||
                   ((tokens.size() == 3) && (tokens[1] == "insert"))) {
                int fileToken = 1;
                if (tokens[1] == "insert") {
                        if (tokens.size() > 2) {
                                fileToken = 2;
                        } else {
                                throw CommandException(
                                        "Missing argument to insert subcommand");
                        }
                }
                try {
                        string filename = userFileContext().resolve(
                                string(tokens[fileToken].getString()));
                        cd.insert(filename);
                        // return filename; // Note: the diskX command doesn't do this either, so this has not been converted to TclObject style here
                } catch (FileException& e) {
                        throw CommandException("Can't change cd image: ",
                                               e.getMessage());
                }
        } else {
                throw CommandException("Too many or wrong arguments.");
        }
}

string CDXCommand::help(const vector<string>& /*tokens*/) const
{
        return strCat(
                cd.name, "                   : display the cd image for this CDROM drive\n",
                cd.name, " eject             : eject the cd image from this CDROM drive\n",
                cd.name, " insert <filename> : change the cd image for this CDROM drive\n",
                cd.name, " <filename>        : change the cd image for this CDROM drive\n");
}

void CDXCommand::tabCompletion(vector<string>& tokens) const
{
        static constexpr const char* const extra[] = { "eject", "insert" };
        completeFileName(tokens, userFileContext(), extra);
}


template<typename Archive>
void IDECDROM::serialize(Archive& ar, unsigned /*version*/)
{
        ar.template serializeBase<AbstractIDEDevice>(*this);

        string filename = file.is_open() ? file.getURL() : string{};
        ar.serialize("filename", filename);
        if (ar.isLoader()) {
                // re-insert CDROM before restoring 'mediaChanged', 'senseKey'
                if (filename.empty()) {
                        eject();
                } else {
                        insert(filename);
                }
        }

        ar.serialize("byteCountLimit",         byteCountLimit,
                     "transferOffset",         transferOffset,
                     "senseKey",               senseKey,
                     "readSectorData",         readSectorData,
                     "remMedStatNotifEnabled", remMedStatNotifEnabled,
                     "mediaChanged",           mediaChanged);
}
INSTANTIATE_SERIALIZE_METHODS(IDECDROM);
REGISTER_POLYMORPHIC_INITIALIZER(IDEDevice, IDECDROM, "IDECDROM");

} // namespace openmsx